Daylight loading roll film developing tank



Ill/fl A. W. BALLUFF- Filed May 12, 1948 DAYLIGHT LOADING ROLL FILM DEVELOPING TANK Aug. 7, 1951 Patented Aug. 7, 1951 T `OFFICE DAYLIGHT LOADING ROLL FILM -DEVELOPING TANK Ameri W. Bauufr, chicago, In. Application May 12, 1948, Serial No. 26,593

(Cl. S35-90.5)

5 Claims. 1

My invention relates to an improved daylight loading roll film developing tank.

Attempts have heretofore been made Yto construct a complete roll lm developing tank capable of receiving a roll of ordinary roll camera film and developing that film without the use of a darkroom or light-tight changing bag.v However, such devices have not been practical for use by average persons because they depend on complicated and expensive mechanisms and require expert; manipulation. For this reason, the film developing-tanks that. have enjoyed substantial use have been of the type requiring .a

darkroom or light-tight changing bag .for loading.V

' Itis, accordingly, a general object of the present invention to providev an-improvedfdaylight loading roll lm developing tank lsuitable for use by the average person. s f A morespeciiic object of the presentinvention is `to yprovide an improved daylightloading roll lm developing tank which may be manipulated inv a manner similar to a roll film camera, to the end that the average camera user will have the skills requisite `to the operation of the device.

Still another object of. the present'l -invention is to provide an improved daylight loading roll film developing tank having vloading mechanism similar vto the 'loadingmechanism of a conventional camera, f Y Another object .of .the present invention is vto provide an'improved daylight loading roll lm developing tank having integral means to sepa-V ratethe lfilm from thefbacking portion thereof.

vMy invention further residesin providing any improved .daylight loading roll film developing tank having features of construction, combina-A tion, and arrangement rendering it simple in construction and reliable in operation to the end that a rugged structure of minimum expense havingk maximum utility is provided. s

acteristic of my invention are set forth with particularity in the appended claims. My invention,

itself, however, both as toits organization and,

method of operation, together with further objects Aand advantages thereof, may best be understood by reference to the following description taken in connection with the accompanying drawing in which:

Figure 1 isl a side elevational view-of a roll lm developing tank constructed thefeatures Of the present invention;

g-FlgureZ isga cross sectional view through the axis 2-.-2, Figure 1,l showing the tank in the loadine condition; f

in accordance withV Y. 40 `The novel features whichlbelieve to be charf` Figure 3 is a view like Figure 2 but showing the tank in the developing condition;

Figure 4 is a cross sectional view through the axis 4 4, Figure 3; and

Figure 5 is an enlarged fragmentary view showing how the film is cut from the backing..

Figure 6 is a fragmentary cross sectional view through the axis 6-6, Figure 4;

Figure 7 is a fragmentary top plan View of the cup-shaped knob receiving portion of the structure of Figure l and showing the indexing keyways formed therein.

Referring to Figure l, there is shown a housing adapted to receive roll film. This housing in- Cludes a receptacle portion R dened by spaced circular top and bottom members I0 and l2 and by the substantially cylindrical side wall I4. A`

closure, shown generally at C, is shiftably mounted on one side of the receptacle R.

The purpose of the receptacle R is to provide a space or cavity I4 for developing the roll iilm whereas the purpose of the closure C is to provide mechanism to insert the lm in the receptacle R without exposing the same to light.

A pair of ilanges II and I3, Figure l, are received within the receptacle R and are mounted on the hollow central shaft I5 to denne a lm receiving spool.

As is best seen in Figures 2 and 3, the top and bottom flanges II and I3 of the spool each have spiral grooves adapted to receive the lm and to guide the same into spaced convolutions suit-able for developing. In the view of Figure 3, the film I8 is shown in the coiled position having spaced convolutions in accord with the grooves of flanges II and I3.

The spool defined by anges II and I3 is held centrally of the cavity of receptacle R by the protuberance I2a in bottom member I2 which rides in a suitable notch in flange II and by the rod I'I which passes through a suitable opening in upper member Il) and is received in the hollow interior of shaft I5.

The cylindrical side wall III has a lengthy film receiving slot 22 at one portion thereof. This slot' is seen in top view in Figure 3 and side view at the broken away portion of Figure 4. This slot is of sufficient length and width to receive the film portion of a roll lm without binding or tearing.

As indicated in Figures 2 and 3, the closure C defines two spaced roll nlm receiving cavities 24 and 26. Each of these cavities is of substantially cylindrical shape and is adapted to receive a roll film in the same fashion as a conventional shape of the camera. A backing panel 28 extends across the closure C and is held against the walls thereof by snap clips 30 which coact with buttons 32 located in Walls 34 and 36.

The cavities 24 and 26 each have central rotatable film receiving posts at each end to engage the spools upon which the iilm is wound. These posts are indicated at 25 and 21 respectively, Figure 2, where they may be viewed throughthe hollow central portions of the spools. Similar posts are provided at the top end of the cavities 24 and 26, as shown in the broken away portion of Figure l Iwhere a post 25 is shown in engagement with a iilm receiving spool 50. The upper posts:`

and 21 extend through the top of cavities 24 and 26 respectively and form knobs 52'whichY may be rotated to Wind the film from oneV cavity to the other.

action is best seen in the greatly enlarged cross sectional view of Figure 5 where the backing portion: of the film is indicated at 66, the film' portion at 68 and the binder tape indicated at 16. As the nlm progresses, the knife 64 rides between binderY tape 10 and the backing portion 66 and The closure C' defines a concave surfacevvhich snugly ts against the surface of the side wall I4 of receptacle R. This surface is formed -by the wall portions 42 and 44. The guides 46 and 48 overlay theA lips 42 and 44 respectively to hold the closure C in mating engagementwith the. side wall. 1.4 ofv receptacle R and to limit the shifting movements of closure C vrelative to receptacle R. Agate 54' automatically closes and opens the slot 22 in accord with the position of closure C relative to receptacle R. As will be evident from the views ofFi'guresgZ and 3, the gate 54 is of arcuate cross section and has its face curved for snug mating engagement withthe curved side wall Iii of the receptacle R. A panel of rubber or similar yielding material, covers the face ofA gate 54 to provide. a fluid tight engagement. Moreover, as. shown in the broken away portion of Figure 4 and in Figure. 6, the. gate E4 extends.

beyond the length. of the slot 22 to provide a. complete seal when in the closed position.

YOpening and closing movements of gate flare guided by the guide channel defined by the upper and lower guideV pieces 56 and 56 and byA the curved lip portion of the sheet metal plate 66. The guide pieces are of identical construction and are positioned to engage the. top and bottom of the gate 54. Moreover, as shown in Figure 2, they engage the back or outer face of the. gate 5d to limit opening movements thereof.

The curved metal plate 6@ is at'ached at its upper and lower ends to the guidepieces. 56 and 56. It extends beyond the edges of these. pieces, as shown in Figure 2, tol define a space tofrecei've, gate :54. The front portieri of gate iid is engaged by the wedgeS-I, Figure 6, to swing the gate to open position and avoid catching of the edge of the gate against the end of the metal plate 6I). If desired, a wedge may be attached to member 16, Figure Li, to supplement the actionV of wedge SII in defining a cam surface to guideA gate 54 into the channel defined by member 6B.

A bar 62 is formed on the side portion I ofv receptacle R and delines a wall against which gate 54 bottoms. In addition, this bar receives the pin 63, Figure 6, which also receives gate 54 to define a hinge. A like pin is provided at the upper end of' bar 62 to hinge the upper end or gate 54.

If desired, springs (not shown) may be provided to urge gate 54 tothe closed position. Thus,V

when the closure C is shifted from the closed po sition of Figure 3 to the open position of Figure 2, the gate 54 swings open as the wedge 6I engagesv the edge thereof to guide the latter in opening movements in the channel defined by guidesv 55 and 5B and the metal piece 66. Y

thus separates'these portions of the film. Since the binder tape 16 is normally attached only to the leading edge of the film as it is wound in the camera, the knifey 64 is required to separate that tape only along the trailingl edge of the film as indicated in Figure 5.

As seen best in Figure 2, the knife l64. bears against the lm as it is wound from cavity 24 to-.cavity 26.

-As thebacking portion 66 of the film is wound in cavity 26, theV lm portion 68 thereof travels through slot 22 and into the cavity defined by receptacle R.

The rod I1 terminates in a handle or knob portion I1a, which protrudes fromi the funnel 12 as', shown in Figure l. At its bottom end this rod is keyed to the shaft I5 to cause rotation of that shaft and theY flanges II and I3 upon rotation of the knob I1a.

When 'thebacking 66 of the film is entirelyV Wound into the cavity 26, vthe handle I1a.V may be rotated to Wind the endof the film portion into the film developing cavity 14 as shown in Figure 3. This action results from the fricjtional' engagements between the flanges II and.

I3 and the film which cause the film to follow the movements of the spool defined by these flanges and the shaft I5.

The closure C may then be shifted to the position of Figure. 3 to close gatev 54 to seal the` cavity 14. 'The film 68 is then in Va sealed cavity in condition for development. l

The film development tank is preferably provided vvithV light tight means to introduce developing iiuids. into cavity 14. Such means are well known to the art and may, for: example, include` a centrally disposed funnel 12 having a tortuous light-tight channel (not shown) communicating with cavity 14. Y

In accordance with a further feature of the present invention, the spool defined by flanges IIV and: I3 is keyed to a predeterminedV position relative to the slot 22 when it is desiredv to load iilm. This position corresponds to that shown in Figure 2 where the grooves on the flanges II and I3 are in position to receive the film portion of the iilm immediately adjacent the slot 22. In other words, the spiral defined by the grooves in these flanges has its open end adjacent the slot 22.

This indexing action is accomplished by the cooperating keyways formed on the cupped surface of the funnel 12 in which the knob I1a rides and the mating keys formed on the lower surface of the knob 11a. The keyways arey the knob Ila is lifted as shown in Figure 1 to free that knob from the keyways and thereby permit rotation.

In this specification and the appended claims, I have used the term backing portion of the film to designate the light-tight backing sheet, usually paper, used in roll nlm to protect the film from exposure to light while loading. I have used the term film portion to designate the transparent portion of the film, usually ce1- lulose acetate, upon which is deposited the light sensitive emulsion. These two portions of the roll lm are usually held together by a suitable binder tape 10, as indicated in Figure 5.

It will of course be understood that the various component elements of the receptacle R and the closure C are joined to form light-tight film handling and developing spaces. This may be done by various methods Well known in the art such as the snug overlapping lips forming joint l5, Figure 1.

When the gate 54 is in the closed position of Figure 3, the members 56 and 58 exert substantial pressure tending to compress the resilient facing 55, thus forming an effective fluid tight seal against escape of developing fluid from the receptacle R.

While I have shown a particular embodiment of my invention, it will, of course, be understood that I do not wish to be limited thereto since many modifications both in the parts themselves and their cooperative structures may be made Without departing from the spirit and scope of my invention. I, of course, contemplate by the appended claims to cover any such modifications as fall Within the true spirit and scope of my invention.

What is claimed is:

1. A daylight loading roll film developing tank comprising a receptacle defining a light-tight cavity having a nlm receiving slot, a gate for said slot mounted for swinging opening and closing movements relative thereto, a closure for said slot mounted for shifting movements relative to said receptacle and adapted to catch the free edge of said gate to open said gate upon predetermined shifting movements in one direction relative to said receptacle, said closure further defining a guide bar to engage the back side of said gate to close said gate upon predetermined shifting movements in the opposite direction relative to said receptacle.

2. A daylight loading roll film developing tank comprising a receptacle defining a light-tight developing cavity having a film receiving opening, a closure defining a light tight space about said opening and shiftably mounted relative to said receptacle, a gate operative to close said opening, said closure having cam surfaces adapted to engage said gate and guide said gate in opening and closing movements as said closure is shifted relative to said receptacle.

3. A daylight loading roll film developing tank comprising a receptacle defining a light-tight cavity having a film receiving slot, a gate for said slot mounted for swinging opening and closing movements relative to said slot, a closure for said slot mounted for shifting movements relative to of said film past said slot, means on said closure adapted to engage the free edge of said gate to open said gate upon predetermined shifting movements of said closure in one direction relative to said receptacle, and means on said closure adapted to engage the back side of said gate to close said gate upon predetermined shifting movements of said closure in the opposite direction relative to said receptacle.

4. A daylight loading roll iilm developing tank comprising a receptacle defining a light-tight f cavity having a film receiving slot, a gate for said slot mounted for swinging opening and closing .movements relative thereto, a closure for said slot mounted for shifting movements relative to said receptacle and defining a light-tight space about said slot, said closure being adapted to receive roll lm and having elements to cause travel of said lm past said slot, means on said closure adapted to engage the free edge of said gate to open said gate upon predetermined shifting movements of said closure in one direction relative to said receptacle, means on said closure adapted to eng-age the back side of said gate to close said gate upon predetermined shifting movements of said closure in the opposite direction relative to said receptacle, and a knife adapted to engage said film at a point adjacent said slot to cut the iilm portion of said film from the backing portion thereof to permit said lm portion to travel through said slot while said backing portion travels past said slot.

5. A daylight loading roll lm developing tank comprising a receptacle defining a light-tight cavity having a film receiving opening, a closure defining a light-tight space about said opening and shiftably mounted relative thereto, a gate adapted to close said opening, means on said closure defining cam surfaces for engagement with said gate to open and close said gate as said closure is shifted relative to said receptacle, means in said closure adapted to receive said film for travel past said opening, a knife adapted to engage said nlm as it travels past said opening to out the film portion therefrom, said closure further defining guide elements to direct said film through said slot.

ALBERT W. BALLUFF.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 728,743 Meek May 19, 1903 1,347,032 Hammond July 20, 1920 1,840,427 Barnack Jan. 12, 1932 FOREIGN PATENTS Number Country Date 44,627 Denmark Sept. 1l, 1931 570,105 Germany Feb. 11, 1933 627,001 Germany Mar. 6, 1936 151,420 Austria Nov. 10, 1937 

